1. Field of the Invention
The present invention relates generally to shelving systems, and more particularly to an improved shelf support system for a "knock-down" type shelving system. The shelf support system of the present invention incorporates a support post having a generally triangular cross-section for efficiently maximizing the available shelf space while providing multidirectional stability to the support system. A single-face snap-on wedge member, having detent means which cooperate with the support post, adjustably locates the wedge member at a predetermined height thereon. A corner bracket, structurally integrable with a corner of the shelf to be supported, is tapered to cooperate with the wedge member, thus to locate and support each shelf corner relative to the wedge member. A collar, structurally cooperating with the corner bracket by a snap-on operation, and forming therewith a generally triangular sleeve about the support post, stably locates and supports the shelf corner at the predetermined height by wedge action, and permits the insertion or removal of a shelf located in the interior of the shelving system, without removing adjacent shelves or partially disassembling the shelving system.
2. Description of the Prior Art
Shelving systems having adjustable height shelves and so called "knock-down" type shelving systems are known, and each has utility in many applications. Further, a knock-down type shelving system which also has adjustable height shelves has great utility in a number of applications, including the food service industry. For example, such shelving systems may be used for efficiently storing and transporting a wide variety of food items, of various sizes, shapes and weights.
Various so called "knock-down" type shelving systems which also have adjustable height shelves are known. In particular, there is known a shelving system utilizing a support post having a polygonal or circular cross-section, and at least one shelf having corner assemblies in which a complimentary bore sleeve) is formed therethrough for receiving the support post. A wedge member is then disposed on each support post, between the support post and the respective bore of the corner assembly, for providing shelf support at a predetermined height of the support post by wedge action therebetween.
U.S. Re. Pat. No. 28,293 relates to such a shelf support system in which a vertical support post has a polygonal cross-section. More particularly, this patent discloses a shelf support system utilizing a support post having a square cross section. A one piece wedge member is adjustably supported on two adjacent sides of the support post by locator means. The locator means includes a series of evenly spaced slots disposed on the support post, and a hooked finger disposed on the wedge member, such that the wedge member may be located at a predetermined height on the support post by hanging the wedge member in a corresponding predetermined slot of the support post by its hooked finger. The complementary hole of the corner structure is designed to define two tapered faces corresponding with, and complementary to, the two tapered faces of the wedge member, such that each tapered face of the shelf corner hole may be seated against a tapered face of the wedge member. In this manner, the shelf is wedged in place relative to the support post substantially at the desired vertical position where the wedge member is disposed on the support post. This design therefore prevents the shelf from dislodging downwardly when a load is positioned on top of the shelf, but permits the shelf to be lifted upwardly from the wedge member if it is desired to adjust the height of the shelf or disassemble the shelf structure. Further, the square cross-section of the support post, having support post walls parallel to the edges of the shelf, provides stability to the shelf support system and the shelving system in those directions.
U.S. Pat. Nos. 3,523,508, 3,874,511, and 4,138,953 all relate to shelving systems utilizing a shelf support system in which the support posts have a circular cross-section. In these shelf support systems, each corner assembly of a shelf is provided with a bore therethrough defining a frusto conical sleeve. A wedge or collar member having a coaxial cylindrical inner bore and a frusto-conical outer face is then disposed around the support post, between the support post and the frusto conical sleeve of the shelf. The wedge member may be formed of two semi-cylindrical halves which mate, and is generally provided with an inwardly projecting bead which mates with a corresponding groove formed in the support post. In this manner, the wedge member, and thus the shelf which is supported thereon by wedge action, is located on the support post at a desired height. Further, as the wedge action operates uniformly in a radial direction in the plane of the shelf, the shelf support system provides multidirectional stability to the shelf support system and the shelving system.
U.S. Pat. No. 3,604,369 also relates to a shelf support system in which the support post has a circular cross section In the patent, a keyway is formed in the sleeve of a shelf corner and mates with a key. The keyway and key are both tapered away from the cylindrical post in a downward direction so as to wedge the sleeve and corner post together when a shelf mounted on the sleeve is assembled with the corner post.
Although each of these systems has great utility in many applications, each suffers a drawback in that the shelf support system does not allow for the insertion or removal of an interior shelf of a plurality of shelves without the removal of adjacent shelves and at least partial disassembly of the overall shelving system. Further, as the corner assemblies of each shelf are designed with a hole therethrough, for reception of the support posts, a tradeoff occurs between available shelf space and the stability of the shelving system. In a "circular" type support system, shelf space is sacrificed by enlarging the circular diameter or moving the hole inwardly to assure the stability of the shelving system. In the "square-hole" type support system, shelf space is sacrificed due to the geometry of the support post, which extends into the interior of the shelf.
Shelving systems in which an interior shelf may be added or removed are known. For example, U.S. Pat. Nos. 4,637,323; 4,615,278; 4,582,001; and 4,079,678 all relate to such systems, which incorporate corner posts and cooperating shelves each having a corner structure that engages a portion of the outer peripheral surfaces of a corner post and interengages with an element that embraces the remainder of the outer peripheral surface of the post in the region of the shelf. These systems are all characterized by difficult assembly since it is inherently difficult to align each of the embracing elements with each of the corner posts and shelf to engage all three components together at the same time.
For these and other reasons, a need exists for an improved shelf support system for a knock-down type shelving system, in which the shelves may be easily adjusted to different heights, and wherein an interior shelf may be inserted or removed from the shelving system without removing adjacent shelves or at least partially disassembling the overall shelving system, and wherein the system may be easily assembled and disassembled both initially and thereafter.